Yzma (The Emperor's New Groove)
Rasputin (Anastasia)
Lord Voldemort (Harry Potter)
Scar (The Lion King)
Judge Claude Frollo (The Hunchback of Notre Dame)
Prince Humperdink (The Princess Bride)
Count Rugen (The Princess Bride)
Cruella De Vil (101 Dalmations)
Syndrome (The Incredibles)
Randall (Monsters Inc.)
Ratigan (The Great Mouse Detective)

Prince Froglip (The Princess and the Goblin)
Darth Traya / Kreia (Star Wars: Knights of the Old Republic 2: Sith Lords video game)
Borg Queen (Star Trek First Contact)
King Haggard (The Last Unicorn)
Sauron (Lord of the Rings)
Red Bull (The Last Unicorn)
Momma Fortuna (The Last Unicorn)
Goblin Queen (The Princess and the Goblin)
Grand Inquisitor Jia (Jade Empire Special Edition video game)
Hexxus (Fern Gully)
Skeksis Lords of the Crystal (The Dark Crystal)
Darth Nihilus (Star Wars: Knights of the Old Republic 2: The Sith Lords video game)
Darth Sion (Star Wars: Knights of the Old Republic 2: The Sith Lords video game)
Death’s Hand (Jade Empire Special Edition video game)
The Yellow-Eyed Demon (Supernatural)
Morganna (Merlin)

When you say Live action, do you mean villains from movies or from series? Had to ask before posting my list.

Ok, here´s my list.

-Hades (Hercules)
-Ernesto De La Cruz (Coco)
-Sanderson sisters (Hocus Pocus)
-Naraku (Inuyasha)
-Kyoka (Fairy Tail)
-Jackal (Fairy Tail)
-Acnologia (Fairy Tail) (Lots of villains, had to choose the worst)
-Bellatrix Lestrange (Harry Potter)
-President Snow (Hunger Games)
-Ego (Guardians of the Galaxy)
-Demogorgon (Stranger Things)
-Joffrey Baratheon (Game of Thrones)
-Ramsay Bolton (Game of Thrones) (I know there are more villains but these 2 are the worst)
-Indominus Rex (Jurassic World)
-Ken Wheatley (Jurassic World: Fallen Kingdom)
-Ramsley (Haunted Mansion)

Nute Gunray (Star Wars)
Rune Haako (Star Wars)
Lotso (Toy Story 3)
Mr. Freeze (Batman the Animated Series)
Penguin (Batman the Animated Series)
Poison Ivy (Batman the Animated Series)
Brain Gremlin (Gremlins 2: The New Batch)
Chucky (Child’s Play Franchise)
Flintheart Glomgold (DuckTales 1987)
Pete (Mickey and Friends)

Jennifer Blake (Teen Wolf)
Zelena Mills (Once Upon a Time)
Regina Mills (Once Upon a Time)
Lord Voldemort (Harry Potter)
Bellatrix Lestrange (Harry Potter)
Mona Vanderwaal (Pretty Little Liars)
Victoria (The Twilight Saga)
Luke Castellan (Percy Jackson and the Olimpians)
President Snow (The Hunger Games)
Morgana Pendragon (Merlin)
Victoria Argent (Teen Wolf)
Lord Shen (Kung Fu Panda 2)
Fairy Godmother (Shrek 2)

Might edit it later...